@gwickstead this post most likely will help you get to your objective.  A quick search for a topic, will most likely find answers to your questions.   

Hi @gwickstead 

I did a little mockup on a form for you.

Basically repeating section with product name, unit price, qty, and line total.

Then outside the repeating section an order total control.

Create a rule for the repeating section.

This uses the current row within the repeating section form controls to multiply and fill the line total value.

pForm].]Repeating section orders].]Current row].]Unit Price]*]Form].]Repeating section orders].]Current row].]Quantity]

Create a form variable to sum the line total. Be sure to selection the line total collection rather than current row.

Lastly create a rule for the form which populates the order total control.

I trigger this by the form variable being filled.

And here is the preview

Cheers,
Gavin

@Gavin-Adams Thanks Gavin, I’ll try this out today and mark this as the best answer when I get it working.

@Sasan I actually did try to search for it, but I wasn’t able to quickly find an answer, but I’ll review your linked search as well.

Thanks Gavin!

Data types were a little finnicky for me as I needed to convert the cost to a number value and then needed to use the rounding function to force a decimal in one location as well, but this totally worked for me!

Thank you!